1. Field of the Invention
The present invention relates to a process for detecting a phenomenon that limits the visibility for a motor vehicle and a detection device enabling the implementation of said process.
The present invention applies in particular to the field of motor vehicles.
2. Description of the Related Art
When applied to a motor vehicle, a process for the detection of a phenomenon limiting the visibility, such as fog, known from prior art, uses a video image to detect high density fog at night. To this end, it uses the luminous halo that forms an ellipse, which is generated by the reflection of headlamps from the fog. Detection of the fog is effected as a function of the parameters of this ellipse.
One problem of this state of the art is that it does not enable fog of a light or medium density to be detected, because fog of this type does not generate a sufficiently visible halo to create an ellipse when it is illuminated by the vehicle's headlamps, with the result that such a halo cannot be used for the detection of fog.